The present invention relates to a tape sensor system that monitors the tape application by taping machines to boxes.
The use of pressure-sensitive adhesive tape for the purpose of sealing boxes, and more specifically box flaps, is generally known. Moreover, it is known that cartons or boxes which are continuously moved along a conveyor can be automatically sealed by such adhesive tape.
Box sealing machines have been developed for applying lengths of tape to boxes as they are moved through such machines in a continuous manner. Moreover, such box sealing machines are known to be provided as part of a packaging line where the boxes are fed continuously to the box sealing machine from which the sealed boxes are further conveyed for further processing, such as palletizing, shipping, etc. Boxes are typically sealed on one or more sides, and such box sealing machines typically provide taping heads of a number corresponding to the number of box sides to be sealed. The taping heads may be arranged to seal the top and bottom box flaps, opposite side flaps, or any combination thereof.
Such box sealing machines, like any other machine within the packaging line, when down, have the potential to slow down or even stop the entire packaging line. Thus, it is beneficial to minimize such down time. Unless the adhesive tape is supplied to the box sealing machine by a continuous tape supply that is of indefinite length, the box sealing machine will need to be stopped on a regular basis to change tape supply rolls. Minimizing other down time is highly desirable.
It is not only important to minimize machine down time, it is also important to minimize improper taping and sealing of boxes. Further in this regard, it is desirable to detect any improper taping or other errors within the packaging line so that it can be corrected as soon as possible. Of course, the longer that it takes to detect such error, the more boxes that are improperly sealed and which must be redone.
The monitoring of equipment in general as well as the monitoring of product exiting any production line for quality purposes is well known. Such monitoring includes the use of a wide variety of inspection systems which rely on many different kinds of sensors depending on the object being monitored. Typical sensors include cameras, optical sensors, mechanical sensors, magnetic sensors, electrical sensors, and the like, which are typically provided as part of a controlled system which includes a feedback loop or circuit which may control such processing equipment. Moreover, it is generally known that if certain errors are detected, machines may be actually shut down until a correction is made. Examples of labeling machines having sensing systems which disable certain machine functions upon the detection of a missing label are described in U.S. Pat. Nos. 4,687,535 (Voltmer) and U.S. Pat. No. 3,989,574 (Evans).
With regard to box sealing machines, it is well known to use a variety of sensors, such as mechanical switches, optical sensors, photo cells, electrical switches, and the like, to control the taping operation of a box driven through such machine. Typically, such sensors detect the position of the box as it is moved through the machine and controls specific taping operations based on the detected box position. Examples of such taping machines including control sensors can be found in U.S. Pat. Nos. 4,846,921 (Lerner et al.); U.S. Pat. No. 4,836,873 (Mitanihara et al.); U.S. Pat. No. 4,640,731 (Lerner et al.); U.S. Pat. Nos. 4,585,504, 4,554,042, and 4,538,398 (Marchetti); and U.S. Pat. No. 4,548,022 (Yaklia). The sensing systems of these machines, however, are not provided with the sensing error conditions. Moreover, they do not provide a feedback for disabling any function of the machines.
On other box sealing machines, a variety of sensors are integrated directly into the taping unit, taping head, or taping applicator. (See, for example, U.S. Pat. No. 4,855,006 (Marchetti); electrically controlled U.S. Pat. No. 5,507,907 (Kropp et al.); and U.S. Pat. No. 5,735,101 (Belcor)).
In another example, a sensor system for use with a “taping head” is provided to sense the tape feed so that it is possible to stop the machine if the tape feed ceases (i.e., supply tape is depleted or tape breaks) or continues to dispense (i.e., tape does not cut). A dispensing sensor is positioned along the “tape guide path” of the “taping head” for determining whether tape is being dispensed from the taping head. A sensor is positioned on the taping head for indirectly determining whether an object is present for taping and a control system is connected to the tape dispensing sensor and an object sensor is used in determining a potential error condition.
In another example, a tape management system for use in a “taping applicator” is provided to sense the tape feed so that it is possible to stop the machine if the tape feed ceases or continues to dispense. Sensors are mounted on to the taping applicator where a detector having a feeler arm is positioned to bear against the tape on the tape path when the front roller is moved into the sensing position. The detector system can detect the tape and activate a warning system in the event no tape is detected or sense when the tape cutter has failed to cut the tape.
Another approach has been to mount sensors directly onto the box-sealing machine whereby the sensors look directly at the presence of the tape media. This approach provides information on the presence (or no presence) of tape, but does not provide any information on whether the tape is moving.